INTRODUCTION: EDF is proposing to construct two EPR nuclear power on the Suffolk coast. However, the Joint Response of Suffolk Coastal District Council and Suffolk County Council to EDF Energy’s Stage 3 Public Consultation of 26 March 2019 indicates the view that EDF’s published plans for Sizewell C do not show adequate protection from coastal erosion or flood risk over the site life. Nor is the design, either with an element of failsafe capacity or capability of future adaptation, future-proofed against the ramping effects of climate change.

The Councils note that the sea defences proposed are inadequate, observing that EDF has given a misleading impression of the seaward extent of the hard-coastal defence feature (HCDF) and that there will be an unknown impact on the coastline and coastal processes caused by the proposed footprint of Sizewell C being further seaward than Sizewell B.

This paper will look at the offshore Sizewell coralline banks which are regarded as key to Sizewell C’s security and coastline micro-stability, in order to review whether they can be regarded as stable over the timescale considered to be the lifetime of the plant. It will also consider the effects of sea level rise on the banks’ relative effectiveness at mitigating storm surges onto the Sizewell C foreshore. The combined effect of these processes suggests that the Sizewell C coastline is considerably more vulnerable than EDF suggest. Indeed, there is good evidence to indicate that, in the lifespan of the nuclear plant, the Sizewell complex may be subject to ‘islanding’ – i.e. it will regularly be surrounded by flood water.

In short, this paper will examine EDF’s assumption that the Sizewell coast is stable enough to defend against the ramping effects of climate change, or whether this claim represents a highly selective interpretation of expert evidence.